Your corporation will need to get an employer identification number (FEIN or EIN) for its federal tax filings, and you’ll likely need an EIN to open a corporate bank account, apply for state licenses and permits, and more generally to establish your corporation’s credibility with potential clients and vendors. You can apply for an EIN by filing Form SS-4 with the IRS online, by fax, or by mail.

Everything you need to know about getting an EIN.